how much air to cause damage

When i draw test from the amp i'm not able to get all the air out. It has very tiny air bubbles. Do other people have this problem? And i wanted to know how much air does it take to cause damage to your body?

With venous air emboli, case reports have found the lethal volume to be on the order of 200-300 mL. One study reports that 3-8 mL/kg is enough to cause acute right ventricular outflow obstruction and death. This is the primary cause of sudden death in patients with major venous air emboli. Essentially, the air gets pumped into the pulmonary arteries, and obstructs further flow of deoxygenated blood into the lungs.

hope this clears this thread up

Technically known as cases of "air embolism". The word embolism comes from Greek en, "in," and ballein, "to throw or cast". Henceforth we will be using the term "air embolism".

Before telling anything further about death by air embolism, let us first understand a little bit about the way our blood circulates in our body. This is very essential to understand how a person is killed by injection of air. Our heart is comprised of 4 chambers. There are two chambers on the right and two on the left side. The chambers on the right side are known as right atrium and right ventricle, while the chambers on the left side are known as left atrium and left ventricle. Bad blood (deoxygenated) from legs, head, arms and in fact from every part of the body returns to the upper right chamber called the right atrium.

With each contraction of the heart the right atrium sends this bad blood to the right ventricle. The right ventricle, in turn, sends this blood to the lungs via pulmonary arteries. Do not let the complicated names baffle you. Just remember that atrium and ventricles are fancy sounding names of some chambers of the heart. Ventricle is a larger chamber than atrium. Also keep in mind that "artery" is the name of a conduit which takes the blood away from the heart while vein is the name of a conduit which brings blood to the heart. The word pulmonary comes from Latin pulmo, "the lung". Thus "pulmonary artery" refers to a conduit which takes the blood away from the heart towards the lung.

In the lung, the bad blood is purified (oxygenated). This is done by the help of the air which we breathe all the time. The pure blood is returned to the heart via pulmonary veins. The blood comes in the third chamber of the heart known as left atrium. Left atrium sends this blood to the left ventricle, which in turn, pumps this pure blood to the whole body via a very big conduit known as the aorta. The body organs use this pure blood, and when this blood becomes impure, it is once again returned to the right atrium. And thus the circulation goes on.
Now we are ready to understand how air embolism works. First of all we must appreciate that nature has made this whole system of circulation air-proof. This means that there is no way, air could enter this system of conduits and pipes. If somehow air could enter the system (such as by injection of plain air through a syringe), the air will form an "air lock" within the system. This "air lock" is quite familiar to plumbers and owners of diesel engines, where the normal flow of liquid through tubes is wholly or partially blocked by air. Quite in the same manner this air lock blocks the flow of blood through the arteries and veins, thus bringing the circulation to a halt. Let us make this a little more clear.

Air could be made to enter the circulation either through the arteries or through the veins. When an injection of air is given, the air bubbles start travelling towards the right atrium. From right atrium they keep travelling onwards till they come to the lung. Here the capillaries are too narrow to allow the big bubbles to pass. The result is that these bubbles get entangled in the blood vessels of the lung. The whole blood traffic stops and the person dies very quickly. In fact this bad blood can not be purified by the lungs, because the traffic of blood towards the lungs has been stopped. The body can not imagine that such a sinister thing has happened. It "thinks" that the blood is not getting purified because of lack of air. So it quickens the respiration. The person starts gasping. But nothing helps because the cause lies somewhere else and the person dies.

Now this is where discrepancies lie…in how much is needed. This article cited 200 mL (cc’s), which I think is an exaggeration. Other articles I have come across state wide ranges…anything from 20 mL to the above mentioned 200. I say about 20 mL, as an educated guess…and I read that in some nursing journal during schooling as well. 20 mL is approximately the length of an IV line…so those who’ve been in hospital can now envision how much is needed.

Now this is where discrepancies lie…in how much is needed. This article cited 200 mL (cc’s), which I think is an exaggeration. Other articles I have come across state wide ranges…anything from 20 mL to the above mentioned 200. I say about 20 mL, as an educated guess…and I read that in some nursing journal during schooling as well. 20 mL is approximately the length of an IV line…so those who’ve been in hospital can now envision how much is needed.

I've seen IVs given where the whole IV line has ran out and a new bag put on without bleeding the line first and the person was no worse for the wear. This has happened on SEVERAL occasions and nothing has happened to the people in any of these cases. So if 20 mL can kill somebody then it hasn't happened when I was around...

The problem with the "article" you posted, paintball, was that it was written by a nurse that cited no reference material and was merely making an "educated guess". Oh, wait. …and she read that in some nursing journal during schooling as well. Basically a dose of 50 mL has been shown to cause problems like severe hypertension.

Volume of Air in a Lethal Venous Air Embolism Is Related to Cardiac Stroke Volume
Yi Chang, M.D., Gong-Jhe Wu, M.D., Tsung-Ying Chen, M.D., Mark I. Rossberg, M.D., Thomas J.K. Toung, M.D.
Department of Anesthesiology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan.
Introduction: The cause of death from venous air embolism (VAE) is due to cardiac dysfunction subsequent to right ventricular ischemia and/or right ventricular outflow obstruction. The lethal volume of air in a dog is reported to be 7.5 ml/kg, which when translated to a 70 kg man and 3 kg rabbit would be approximately 525 ml and 22.5 ml respectively. These volumes are far greater than reported lethal volumes of 200 ml in man and 2.25 ml in rabbit. Children have been noted to suffer greater hemodynamic derangement from VAE than adults. This is believed to be related to the volume of air entrained, which in children is larger relative to their cardiac volume. We proposed that the lethal volume of air is probably more closely related to the cardiac stroke volume than to body weight. We tested the hypothesis in a rat model of venous air embolism.

Methods: Thirty-five spontaneously breathing halothane-anesthetized (1.0-1.5% halothane in air-oxygen mixture) male Wistar rats (250-480 gm) were studied. Right femoral arteries were cannulated for blood pressure and left external jugular veins were used for injection of air. In the supine position, each rat received a single dose of air. Injected volumes of air were 0.2, 0.22, 0.24, 0.25 ml and thereafter incremental volumes of 0.05 ml to 0.4 ml. These numbers were based on the measured cardiac stroke volume of 0.32 &#177; 0.06 ml by Wicker et al. A 10 min waiting period following injection was allowed before examination.

Results: Femoral blood pressure fell precipitously when air was injected. All rats survived 0.2 ml volume injection, however, all rats that received an air volume of 0.3 ml or greater died. Death occurred within one to three minutes after injection. The log dose of air volume and the death rate is plotted as in figure 1. The calculated LD50 is 0.23 ml.

Conclusions: The volume of air required to cause death in a rat is equivalent to one stroke volume. Such a relationship between VAE and stroke volume may apply in man.

Um, you'd need a bunch.

Everything I've seen or heard pretty much leads me to believe you need at least a few cc's of air to cause problems. Unless your really dumb, getting that much air into your vein should be pretty tough.